Cherokee 140 wheel pants restricting access to valve stems

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RonP

Pre-takeoff checklist
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I have a 1969 Cherokee 140 with wheel pants. The tube valve stems are not right angle and stick up inside the rim. To put air in the tires I have to remove the outboard fastener, loosen the two inner fasteners and painfully reach inside the wheel pants to get the air chuck on. Short of completely removing the wheel pants or the technique described above to check or add air is there a special technique or air chuck that would eliminate the extra labor?
 
You just have to attach a 7/16" socket to your vari-speed drill and go after the job. There is no shortcut. After a couple of times you'll be able to do all three wheel pants off-air-on in about 20 minutes.
 
Not at right angles? Perhaps the inner tubes need to be properly re-installed. I took off the wheel pants in 2004 and never put them back on. They’re sitting on a shelf in the hangar. The alleged 2-3 kts improvement on the cherokee isn’t worth the aggravation. On top of that, no chance of water/snow turning to ice under the wheel pants in the winter or dirt/weeds in the summer to interfere with the brakes.
 
Thanks for the suggestions. The dual air chuck may work using the head that is at an angle. Right angle valve stems cannot be used on the tubes including valve stem extensions. Anything that is less than the thickness of a finger between the rim and the wheel pants would hit the side of the wheel pants when the wheel rotates. Even if such a tube were made with a stubby right angle valve stem short enough to not interfere with the wheel pants there would not be enough length for a Schrader valve to be inserted into the valve stem.

One reply stated the inner tubes need to be properly reinstalled. If they know of a tube with a right angle valve stem that does not protrude more than about 1/4" from the rim please let me know. It would be worth it to me at next annual (or sooner) to have those tubes installed. Appreciate the information and anxiously awaiting the information.

Last resort is to break out the 7/16" wrench and take my time as I have been doing.

Lastly I have no clue if the wheel pants increase my cruise speed or not and that is not significant enough for me to debate. My only reason for keeping them is to cut down on dirt/grime/etc being thrown onto the struts. In my rental days I rented a Warrior and an Archer. The Warrior had wheel pants and the struts always seemed to be shiny clean. The Archer did not have wheel pants and there was always dirt and grime on the struts that I would clean before flying so it would not grind away on the seal. That was my observation and the only visible difference was the wheel pants on the Warrior. It may be a false conclusion but I am sticking with it since the Cherokee came with wheel pants I am going to keep them on until they are no longer functional.

Thanks everyone for the advice.
 
I've seen holes drilled (requires moving plane to line them up, and notches cut (requires moving, again). Would this work?
159141_2000x2000.jpg
 
In the experimental world, many drill ~1" holes and use a valve stem extension to access the valve.

Here's a valve stem extension:

https://www.amazon.com/Milton-S-440...0449215&sr=8-18&keywords=valve+stem+extension

All you do is insert it through the hole in your wheelpant, screw it onto the valve stem, and then fill the tube as normal except hooking up your air line to the extension outside the wheel pant.

We plug the holes in the wheelpants with snap-in plugs from the aviation aisle at Home Depot.
 
Was just re-reading the replies and my apologies to Skyrys62. I did not fully read his post! He recommended right angle valve stem extensions with the key words:

"If you kept them angled toward the front or back of the plane instead of out to the side"
I had not considered turning the right angle valve stem extensions parallel to the rim/tire, this might actually work! Will have to get some, pull the wheel pants and give it a try. Couple caveats though; (1) will the right angle get it far enough below the wheel pants to access (2) how tight will it attach to the valve stem so it does not move (3) will it touch the axle and the biggest of them all......is this considered a modification that is not legal? Anyone have any insight to the last one?
 
I have this bicycle pump stem adapter (it’s Italian and was like $15 from the bike shop), very small and just thumb screws onto the valve.
I have it pressed into a flexi rubber bike pump hose on a normal bike pump, you can get it into tight spots and just thread it on and add air as needed. For my small uses I just use a manual bike pump with built in PSI gauge.
 
Kenny Phillips said:
I've seen holes drilled (requires moving plane to line them up, and notches cut (requires moving, again). Would this work?
159141_2000x2000.jpg
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That's what I was using until I took off the wheel pants, pretty much permanently.
 
That thing doesn't work for me. The valve stem has to be at 6 o'clock to be accessible and the chuck with the hose attached is too long. As kgruber said, I break out the 7/16".
 
Can you replace the pant fasteners with 1/4-turn SkyBolts or whatever? My friend's RV is set up this way, and he can remove a wheel pant in about 15 seconds. Makes me wish I'd done that...maybe at next annual.
 
SoCal RV Flyer said:
Can you replace the pant fasteners with 1/4-turn SkyBolts or whatever? My friend's RV is set up this way, and he can remove a wheel pant in about 15 seconds. Makes me wish I'd done that...maybe at next annual.
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you don't need that. what else you got to do when you're waiting for the marine layer to burn off. :)
 
Doug Reid said:
Nitrogen might be a good plan as well...Less likely to leak down.
Click to expand...

Interesting timing. I just read this on "another forum" where people talk about airplanes they build at home.

"Given that a tubes permeability to Nitrogen is less then other gases, per the link to the paper in a previous post, wouldn't all of our tires be almost pure Nitrogen as was suggested. The compressed air we fill our tires with is low humidity by virtue of being compressed and starts out as 78% Nitrogen. As the other gases leak out and we refill the tire wouldn't it get to be a higher and higher percent of Nitrogen?"
 
Ravioli said:
you don't need that. what else you got to do when you're waiting for the marine layer to burn off. :)
Click to expand...

That's part of the reason I'm hangared at Cable. :) Most days, the layer doesn't go that far inland.
 
I'm not sure what's different between mine and yours, but on my '66 PA28-140, I can move the plane forward or back, and find there is a very small point where I can get air in the tubes with the pants on...but move the plane 6 inches too far one way or the other, and I can't get to the stems...also, I'm not sure if it is "stock", but I've noticed my wheel pants have a very small (like 1/2 inch by 3 inch) amount of material removed from them right where the valve stems are.
 
Ravioli said:
Interesting timing. I just read this on "another forum" where people talk about airplanes they build at home.

"Given that a tubes permeability to Nitrogen is less then other gases, per the link to the paper in a previous post, wouldn't all of our tires be almost pure Nitrogen as was suggested. The compressed air we fill our tires with is low humidity by virtue of being compressed and starts out as 78% Nitrogen. As the other gases leak out and we refill the tire wouldn't it get to be a higher and higher percent of Nitrogen?"
Click to expand...

It wouldn't appreciably increase the percentage of N2. The nitrogen is leaking, too, just a touch slower...it's not like the O2 seeps out completely first. By the time the tire is worn out and the tube needs to be deflated and reinflated, there would have been very little change in composition. What's more, even if it worked, it would be a case where you lose most of the benefit of the N2 fill by having to wait years until the composition significantly changed.
 
Tawood: my wheel pants do not have any notches in them at all, just a straight line from rear to front on the outboard side where the valve stem is. I will try a few of the suggestion and keep a 7/16 wrench in my back pocket!

Thanks to everyone that replied.
 
RonP said:
Tawood: my wheel pants do not have any notches in them at all, just a straight line from rear to front on the outboard side where the valve stem is. I will try a few of the suggestion and keep a 7/16 wrench in my back pocket!

Thanks to everyone that replied.
Click to expand...
Ok...if I think of it, next time I'm at the hangar I'll take a picture of the bottom of mine (they are removed for winter flying). I wouldn't think it wouldn't take much work to "notch" them...it really isn't even a notch, just a slight "waver" for a few inches along the bottoms. Removing that small amount of material from them sure would make it easier to add/check air.
 
FWIW, my POH (PA-28 181) says the plane gets a 8 kts speed improvement with the pants on. I painted stripes on the wheels to know when fill valve was at bottom and then stretch it for 2-3 seconds to fill/measure.
 
Ravioli said:
Interesting timing. I just read this on "another forum" where people talk about airplanes they build at home.

"Given that a tubes permeability to Nitrogen is less then other gases, per the link to the paper in a previous post, wouldn't all of our tires be almost pure Nitrogen as was suggested. The compressed air we fill our tires with is low humidity by virtue of being compressed and starts out as 78% Nitrogen. As the other gases leak out and we refill the tire wouldn't it get to be a higher and higher percent of Nitrogen?"
Click to expand...

Actually Graham's Law of Effusion predicts that nitrogen (MW 28) will escape faster than oxygen (MW 32). I think the issue is that oxygen reacts with the rubber in the tube, while nitrogen is inert. The consumed oxygen will lower pressure (theoretically). The reality is that gases leak over time, regardless of chemistry. If this was really significant, you could fill your tires with argon (MW 40) which is both heavier and more inert than nitrogen.
 
From the OP’s description, filling the air on a Pa28-181 must be easier but it is still a challenge to get the valve in a position in the little door in the pant and then to bend the stem enough to get the air filler nozzle on the valve stem. Same with the gauge which is made a bit easier depending on the gauge. The biggest issue is often trying to screw off and on the valve cap. Scrapping your fingers still may happen.
I haven’t tried it but painting a mark on the rim to aid valve localization could really help the process.
 
Could someone have installed the wrong inner tube? They come in a variety of different valve stem angles.
 
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